Systems and methods for determining cyclic nucleotide concentration and related pathway activation

The present invention relates in general to cellular analysis tools and more particularly to methods and systems for detecting or determining cyclic nucleotide concentrations and related pathway activation in samples. Samples containing cyclic nucleotides may be contacted with a cyclic nucleotide-dependent protein kinase (e.g., cAMP- and cGMP-dependent protein kinases) and a detection system that includes a substrate capable of being phosphorylated by the cyclic nucleotide-dependent protein kinase. The activity of cyclic nucleotide related cell signaling pathways may be measured based on detecting the activity of the cyclic nucleotide-dependent protein kinase.